Composition for curable resin, cured product of said composition, production method for said composition and said cured product, and semiconductor device

ABSTRACT

The invention relates to a curable resin composition containing (A) a multifunctional benzoxazine compound having two or more benzoxazine rings, (B) an epoxy compound having at least one norbornane structure and at least two epoxy groups, (C) a naphthylene ether type epoxy compound, and (D) a curing agent, and optionally (E) an inorganic filler and (F) a curing accelerator; a cured product thereof; methods of producing the curable resin composition and the cured product and a semiconductor device in which a semiconductor element is disposed in a cured product obtained by curing a curable resin composition containing components (A) to (D), and optionally components (E) and (F).

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2017-208606, filed on Oct. 27, 2017; theentire contents of which are incorporated herein by reference.

TECHNICAL FIELD

The present invention relates to a curable resin composition forobtaining a cured product high in heat resistance, a cured productthereof, and methods of producing the curable resin composition and thecured product. Furthermore, the present invention relates to asemiconductor device using the cured product as a sealant.

BACKGROUND ART

Curable resins are used in various applications of semiconductorsealants, fiber reinforced plastics, and the like, and benzoxazinecompounds are used for one of raw materials of such resins.

Benzoxazine compounds refer to compounds each including a benzoxazinering having a benzene backbone and an oxazine backbone, and benzoxazineresins as cured products (polymerized products) thereof are excellent inphysical properties such as heat resistance and mechanical strength, andare used as high-performance materials in various applications.

Patent Literature 1 discloses a novel benzoxazine compound having aspecified structure, and a production method thereof, and describes thebenzoxazine compound which has a high thermal conductivity and whichenables a benzoxazine resin cured product having a high thermalconductivity to be produced.

Patent Literature 2 discloses a thermosetting resin where a reactive endof a polybenzoxazine resin having a specified benzoxazine ring structurein a main chain is partially or fully dosed, and describes thethermosetting resin which is excellent in storage stability in the caseof being dissolved in a solvent.

RELATED ART DOCUMENTS Patent Literature

[Patent Literature 1] JP 2013-60407 A

[Patent Literature 2] JP 2012-36318 A

SUMMARY OF THE INVENTION Problems to be Solved by the Invention

There is still a need for a resin cured product that is more excellentin heat resistance and high-temperature stability so as to be adaptedfor more stringent usage conditions, in applications of, for example,matrix resins for adhesives, sealants, paints, and composites. There isa need for a curable resin composition for obtaining a cured productthat is excellent in high-temperature stability, particularly inapplications of a semiconductor device and the like where much higherreliability is demanded.

However, there has not been obtained any curable resin composition forobtaining a cured product that is excellent in high-temperaturestability although high in heat resistance.

Accordingly, an object of the present invention is to provide a curableresin composition for obtaining a cured product that is excellent inhigh-temperature stability although high in heat resistance. Anotherobject of the present invention is to provide a cured product obtainedby curing the curable resin composition, and methods of producing thecurable resin composition and the cured product. Another object of thepresent invention is to provide a semiconductor device using the curedproduct as a sealant.

Means for Solving the Problems

The present inventors have made intensive studies in order to achievethe above objects, and as a result, have developed a curable resincomposition containing a multifunctional benzoxazine compound andspecific two kinds of epoxy compounds, and have found that a curedproduct of the curable resin composition is excellent in heat resistanceand high-temperature stability, thereby leading to completion of thepresent invention.

That is, the present invention is as follows.

[1] A curable resin composition, containing:

(A) a multifunctional benzoxazine compound having at least twobenzoxazine rings, the compound being at least one multifunctionalbenzoxazine compound selected from a multifunctional benzoxazinecompound having a structural unit of formula (1) and a multifunctionalbenzoxazine compound represented by a structure of formula (2),

(B) an epoxy compound having at least one norbornane structure and atleast two epoxy groups,

(C) a naphthylene ether type epoxy compound, and

(D) a curing agent;

wherein in the formula (1), R represents a linear alkyl group having 1to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, oran aryl group having 6 to 14 carbon atoms, where the aryl groupoptionally has halogen or a linear alkyl group having 1 to 12 carbonatoms, as a substituent; and each Z represents hydrogen, a hydrocarbongroup having 1 to 8 carbon atoms and/or a linking group and isoptionally the same or different, at least one Z represents a linkinggroup, and benzoxazine rings are linked by the linking group;

wherein in the formula (2), L represents a divalent organic group having1 to 5 aromatic rings or an alkylene group having 2 to 10 carbon atoms,and the organic group and the alkylene group optionally comprise oxygenand/or sulfur

[2] The curable resin composition according to [1], wherein (C) thenaphthylene ether type epoxy compound is an epoxy compound representedby a structure of formula (3):

wherein in the formula (3), n is an integer of 1 to 20; l is an integerof 0 to 2; substituents R₁ each independently represents a benzyl group,an alkyl group or a structure represented by formula (3a); and R₂independently represents a hydrogen atom or a methyl group;

[wherein in the formula (3a), Ar each independently represents aphenylene group or a naphthylene group; R₂ each independently representsa hydrogen atom or a methyl group; and m is an integer of 1 or 2].

[3] The curable resin composition according to [1] or [2], furthercontaining (E) an inorganic filler.

[4] The curable resin composition according to any of [1] to [3],further containing (F) a curing accelerator.

[5] A cured product obtained by curing the curable resin compositionaccording to any of [1] to [4].

[6] A semiconductor device, wherein a semiconductor element is disposedin a cured product obtained by curing the curable resin compositionaccording to any of [1] to [4].

[7] A method of producing a curable resin composition, the methodcomprising the steps of: mixing

(A) a multifunctional benzoxazine compound having at least twobenzoxazine rings, the compound being at least one multifunctionalbenzoxazine compound selected from a multifunctional benzoxazinecompound having a structural unit of formula (1) and a multifunctionalbenzoxazine compound represented by a structure of formula (2),

(B) an epoxy compound having at least one norbornane structure and atleast two epoxy groups,

(C) a naphthylene ether type epoxy compound, and

(D) a curing agent;

to obtain a mixture; and

processing the mixture into a powdery, pelletized, or granular curableresin composition;

wherein in the formula (1), R represents a linear alkyl group having 1to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, oran aryl group having 6 to 14 carbon atoms, where the aryl groupoptionally has halogen or a linear alkyl group having 1 to 12 carbonatoms, as a substituent; and each Z represents hydrogen, a hydrocarbongroup haying 1 to 8 carbon atoms and/or a linking group and isoptionally the same or different, at least one Z represents a linkinggroup, and benzoxazine rings are linked by the linking group;

wherein in the formula (2), L represents a divalent organic group having1 to 5 aromatic rings or an alkylene group having 2 to 10 carbon atoms,and the organic group and the alkylene group optionally comprise oxygenand/or sulfur.

[8] The production method according to [7], wherein (C) the naphthyleneether type epoxy compound is an epoxy compound represented by astructure of formula (3):

wherein in the formula (3), n is an integer of 1 to 20; l is an integerof 0 to 2; substituents R₁ each independently represents a benzyl group,an alkyl group or a structure represented by formula (3a); and R₂independently represents a hydrogen atom or a methyl group;

wherein in the formula (3a), Ar each independently represents aphenylene group or a naphthylene group; R₂ each independently representsa hydrogen atom or a methyl group; and m is an integer of 1 or 2].

[9] The production method according to [7] or [8], wherein the step ofobtaining the mixture includes further mixing (E) an inorganic fillerand/or (F) a curing accelerator to obtain a mixture.

[10] A method of producing a cured product, the method comprising

a step of heating the curable resin composition produced by the methodaccording to any of [7] to [9], at 150 to 300° C. for 20 seconds to 1hour for curing.

Effects of the Invention

The curable resin composition of the present invention is a novelcurable resin composition containing components (A) to (D), and further,if desired, components (E) and (F), and a cured product of thecomposition is characterized by being excellent in heat resistance andhigh-temperature stability. Furthermore, the curable resin compositionis characterized by being excellent in dimensional stability.Accordingly, the curable resin composition of the present invention canbe used in an application where high heat resistance, high-temperaturestability, and if desired, dimensional stability are required, forexample, applications of matrix resins for adhesives, sealants, paints,and composites. In particular, the curable resin composition not onlycan allow a semiconductor element sealant to exert excellent sealingperformance, but also can contribute to high reliability of asemiconductor device.

MODE FOR CARRYING OUT THE INVENTION

[Curable Resin Composition]

Hereinafter, the present invention will be described in detail. It isnoted that each “compound” in components (A) to (C) in the presentinvention encompasses not only a monomer represented in each formula,but also an oligomer obtained by polymerization of a small amount of themonomer, namely, a prepolymer before formation of a curable resin.

(Component A)

The component (A) that constitutes the curable resin composition is atleast one multifunctional benzoxazine compound having at least twobenzoxazine rings, selected from a multifunctional benzoxazine compoundhaving a structural unit of formula (1) and a multifunctionalbenzoxazine compound represented by a structure of formula (2). Herein,each Z in the formula (1) represents hydrogen, a substituent and/or alinking group (spacer), and is optionally the same or different, atleast one Z represents a linking group, and benzoxazine rings are linkedby the linking group. The linking group here encompasses two benzoxazinerings directly bound via no other group. Examples of the substituentinclude a hydrocarbon group having 1 to 8 carbon atoms.

Accordingly, the formula (1) represents the structural unit of anycompound where two or more benzoxazine rings are linked at a benzenering moiety, among options of the component (A).

The multifunctional benzoxazine compound of formula (1) can be morespecifically represented as having a structure represented by formula(1a):

wherein in the formula (1a), R represents a linear alkyl group having 1to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, oran aryl group having 6 to 14 carbon atoms, where the aryl groupoptionally has halogen or a linear alkyl group having 1 to 12 carbonatoms, as a substituent; each R is optionally the same or different;each X represents hydrogen or a hydrocarbon group having 1 to 8 carbonatoms, and is optionally the same or different; Y represents an alkylenegroup haying 1 to 6 carbon atoms, oxygen, sulfur, a SO₂ group, or acarbonyl group; m is 0 or 1; and n is an integer of 1 to 10.

Specific examples of R in formulae (1) and (1a) can include thefollowing groups.

Examples of the linear alkyl group having 1 to 12 carbon atoms include amethyl group, an ethyl group, a propyl group, an isopropyl group, ann-butyl group, an isobutyl group, and a t-butyl group.

Examples of the cyclic alkyl group haying 3 to 8 carbon atoms include acyclopentyl group and a cyclohexyl group.

Examples of the aryl group having 6 to 14 carbon atoms include a phenylgroup, a 1-naphthyl group, a 2-naphthyl group, a phenanthryl group, anda biphenyl group.

The aryl group having 6 to 14 carbon atoms is optionally substituted,and examples of the substituent include a linear alkyl group having 1 to12 carbon atoms, or halogen. Examples of the aryl group having 6 to 14carbon atoms, substituted with a linear alkyl group haying 1 to 12carbon atoms, or halogen include an o-tolyl group, a m-tolyl group, ap-tolyl group, a xylyl group, an o-ethylphenyl group, a m-ethylphenylgroup, a p-ethylphenyl group, an o-t-butylphenyl group, am-t-butylphenyl group, a p-t-butylphenyl group, an o-chlorophenyl group,and an o-bromophenyl group.

R is preferably selected from a methyl group, an ethyl group, a propylgroup, a phenyl group, and a p-tolyl group from the viewpoint offavorable handleability.

The component (A) may also be a mixture of a plurality of kinds ofcompounds represented in formula (1) or (1a), which are different in Rfrom each other.

Examples of the hydrocarbon group having 1 to 8 carbon atoms as X informulae (1) and (1a) include an alkyl group, an aryl group, and anaralkyl group, and an aryl group is preferable.

Examples of the multifunctional benzoxazine compound represented byformula (1) or (1a) can include a compound represented by the followingformula (1X) and an oligomer obtained by polymerization of a smallamount of the compound.

The multifunctional benzoxazine compound of formula (2), as other optionof the component (A), is a compound where respective nitrogen atoms (Natoms) in two benzoxazine rings are bound via a linking group L,

wherein in the formula (2), L represents a divalent organic group having1 to 5 aromatic rings or an alkylene group having 2 to 10 carbon atoms,and the organic group and the alkylene group optionally comprise oxygenand/or sulfur.

The composition of the present invention may contain a plurality ofkinds of multifunctional benzoxazine compounds represented by formula(2), which are different in L, in the component (A).

In the case where L in formula (2) represents an aromaticring-containing group, the group contains 1 to 5 aromatic rings, andexamples thereof include a monocyclic compound, a multicyclic compound,and a fused ring compound. L may also comprise at least one selectedfrom the group consisting of oxygen and sulfur.

Specific examples can include a group represented by the followingformula (2a).

In the case where L in formula (2) represents an alkylene group, thealkylene group has, for example, 1 to 10 carbon atoms, preferably 1 to 6carbon atoms. Specific examples of the alkylene group include amethylene group, an ethylene group, and an isopropylidene group, andpreferably include a methylene group.

Examples of the multifunctional benzoxazine compound of formula (2) caninclude a compound represented by the following formula (2X), and anoligomer obtained by polymerization of the compound, for example, anoligomer obtained by polymerization of a small amount of the compound.

Any commercially available product can also he used as themultifunctional benzoxazine compound in the component (A). Examples ofsuch any commercially available product can include bisphenol F-aniline(F-a)-type benzoxazine and phenol-diaminodiphenylmethane (P-d)-typebenzoxazine (both are manufactured by SHIKOKU CHEMICALS CORPORATION)

(Component B)

The component (B) that constitutes the curable resin composition is anepoxy compound having at least one norbornane structure and at least twoepoxy groups (hereinafter, also simply referred to as “multifunctionalepoxy compound”). The composition of the present invention may contain aplurality of kinds of the multifunctional epoxy compounds in thecomponent (B). The epoxy compound is preferably an alicyclic epoxycompound, more preferably has an epoxy structure represented by thefollowing formula (4), bound to a 5-membered ring, a 6-membered ring ora norbornane ring.

Specific examples of the alicyclic epoxy compound can include a compoundrepresented by the following formula (5).

A production example of the multifunctional epoxy compound in thecomponent (B) is described.

A compound of the following formula (5-1) can be produced by, forexample, synthesizing a compound (a) having the following norbornanestructure, by a Diels-Alder reaction of butadiene and dicyclopentadiene,and then reacting the compound (a) and meta-chloroperbenzoic add, asrepresented in the following formula (6).

A compound of the following formula (5-2) can be produced by, forexample, synthesizing a compound (b) (tricyclopentadiene) having thefollowing norbornane structure, by a Diels-Alder reaction ofcyclopentadiene and dicyclopentadiene, and then reacting the compound(b) and meta-chloroperbenzoic add, as represented in the followingformula (7).

A compound of the following formula (5-3) can be produced by, forexample, synthesizing a compound (c) having the following norbornanestructure, by a Diels-Alder reaction of butadiene and cyclopentadiene,and then reacting the compound Cc) and meta-chloroperbenzoic add, asrepresented in the following formula (8).

A compound of the following formula (5-4) can be produced by, forexample, reacting dicyclopentadiene and potassium peroxymonosulfate(oxone). The compound of formula (5-4), dicyclopentadiene diepoxide, mayalso be any commercially available product, and examples of such anycommercially available product can include dicyclopentadiene diepoxidemanufactured by SHANDONG QIHUAN BIOCHEMICAL CO., LTD.

(Component C)

The component (C) that constitutes the curable resin composition is anaphthylene ether type epoxy compound. The naphthylene ether type epoxycompound is preferably an epoxy compound represented by a structure ofthe following formula (3):

wherein in the formula (3), n is an integer of 1 to 20; l is an integerof 0 to 2; R₁ is a substituent, each independently representing a benzylgroup, an alkyl group or a structure represented by formula (3a); and R₂independently represents a hydrogen atom or a methyl group;

wherein in the formula (3a), Ar independently represents a phenylenegroup or a naphthylene group; R₂ independently represents a hydrogenatom or a methyl group; and m is an integer of 1 or 2.

The component (C) may also be a mixture of compounds represented byformula (3), wherein the compounds are different from each other in R₁,R₂, l, and n in the formula.

Examples of naphthylene ether type epoxy compounds represented by thegeneral formula (3) include one represented by formula (3-1):

wherein in the formula (3-1), n is an integer of 1 to 20, preferably aninteger of 1 to 10, more preferably an integer of 1 to 8; and R is asubstituent, each independently representing a benzyl group, an alkylgroup, a structure represented by the following general formula (3a-1),or being absent, where the substituent R is preferably absent;

(wherein in the general formula (3a-4), m is an integer of 1 or 2).

Examples of naphthylene ether type epoxy compounds represented byformula (3-1) include one represented by formulae (3-2) to (3-6):

Any commercially available product can also be used as the naphthyleneether type epoxy compound in the component (C). Examples of commerciallyavailable products of the epoxy compound in the component (C) includeHP-6000 (a tradename; from DIC CORPORATION; having an epoxy equivalentof 235 to 255 g/eq), EXA-7310 (a tradename; from DIC CORPORATION; havingan epoxy equivalent of 237 to 257 g/eq), EXA-7311 (a tradename; from DICCORPORATION; having an epoxy equivalent of 267 to 287 g/eq), EXA-7311L(a tradename; from DIC CORPORATION; having an epoxy equivalent of 252 to272 g/eq), EXA-7311-G3 (a tradename; from DIC CORPORATION; having anepoxy equivalent of 240 to 260 g/eq), and the like. These may be usedsingly or in combination of two or more kinds thereof.

The compounding ratio between the multifunctional benzoxazine compoundin the component (A) and the total of the multifunctional epoxy compoundin the component (B) and the naphthylene ether type epoxy compound inthe component (C) is preferably 5 parts by mass or more and 180 parts bymass or less, more preferably 30 parts by mass or more and 160 parts bymass or less, in terms of the compounding ratio of the total of thecomponents (B) and (C) based on 100 parts by mass of the component (A).

The compounding ratio between the component (A) and the total of thecomponents (B) and (C) can be in the above range, thereby affording acured product more excellent in heat resistance, dimensional stability,and high-temperature stability.

In the case where the composition of the present invention contains aplurality of kinds of the multifunctional benzoxazine compounds in thecomponent (A), the total of such compounds is assumed to be 100 parts bymass. In the case where the composition of the present inventioncontains a plurality of kinds of the multifunctional epoxy compounds inthe component (B), the “compounding ratio of the component (B)” meansthe total ratio of such a plurality of compounds. Further in the casewhere the composition of the present invention contains a plurality ofkinds of the naphthylene ether type epoxy compounds in the component(C), the “compounding ratio of the component (C)” means the total ratioof such a plurality of compounds,

The compounding ratio (mass ratio) of the multifunctional epoxy compoundin the component (B) to the naphthylene ether type epoxy compound in thecomponent (C) is preferably 95:5 to 5:95, more preferably 90:10 to10:90, still more preferably 90:10 to 50:50. The compounding ratiobetween the component (B) and the components (C) can be in the aboverange, thereby affording a cured product more excellent in heatresistance, dimensional stability, and high-temperature stability.

In the case where the composition of the present invention contains aplurality of kinds of the multifunctional epoxy compounds in thecomponent (B), the compounding amount of the component (B) means thetotal compounding amount of such a plurality of compounds. Further inthe case where the composition of the present invention contains aplurality of kinds of the naphthylene ether type epoxy compounds in thecomponent (C), the compounding amount of the component (C) means thetotal amount of such a plurality of compounds.

(Component D)

The component (D) that constitutes the curable resin composition is acuring agent.

Specific examples of the component (D) include aromatic amines (forexample, diethyltoluenediamine, metaphenylenediamine,diaminodiphenylmethane, diaminodiphenylsulfone, metaxylenediamine, andderivatives thereof), aliphatic amines (for example,triethylenetetramine and isophoronediamine), imidazoles (for example,imidazole and imidazole derivatives), dicyandiamide,tetramethylguanidine, carboxylic anhydrides (for example,methylhexahydrophthalic anhydride), carboxylic add hydrazides (forexample, adipic add hydrazide), carboxylic add amides, monofunctionalphenols, multifunctional phenol compounds (for example, bisphenol A,bisphenol F, dihydroxynaphthalene, bisphenol sulfides (for example,bis(4-hydroxyphenyl)sulfide), and a polyphenol compound (for example,pyrogallol)), polymercaptans, carboxylates, and Lewis add complexes (forexample, boron trifluoride ethylamine complex). The component (D) ispreferably at least one selected from imidazoles, aromatic amines, andmultifunctional phenol compounds. These may be used singly or as amixture of two or more kinds thereof.

The compounding ratio of the component (D) is preferably in a range of 1part by mass or more and 30 parts by mass or less, more preferably in arange of 5 parts by mass or more and 25 parts by mass or less, in termsthe compounding ratio of the component (D) based on 100 parts by mass intotal of the components (A), (B), and (C). The component (D) can becontained in such a range, thereby allowing for more efficientprogression of a curing reaction, and obtaining a cured product moreexcellent in heat resistance.

In the present invention, an “epoxy equivalent ratio” in the curableresin composition refers to [the total number of epoxy groups in thecomponents (B) and (C)]/[the number of cyanato groups in the component(A)+the number of hydroxyl groups in the component (D)].

The epoxy equivalent ratio in the curable resin composition ispreferably 0.5 or more and 1.5 or less, more preferably 0.7 or more and1.2 or less. The epoxy equivalent ratio can be in the above range,thereby affording a cured product more excellent in heat resistance,dimensional stability, and high-temperature stability.

(Component E)

The curable resin composition of the present invention may furthercontain, if desired, (E) an inorganic filler.

For example, in the case of use of the curable resin composition of thepresent invention in a sealant application of a semiconductor element orthe like, the component (E) is preferably contained. The inorganicfiller for use in the present invention is not particularly limited, andcan be selected in consideration of an application of the curable resincomposition or a cured product thereof, or characteristics to beprovided. Hereinafter, the inorganic filler is referred to as “component(E)”.

Examples of the component (E) include oxides such as silica, alumina,titanium oxide, zirconium oxide, magnesium oxide, cerium oxide, yttriumoxide, calcium oxide, antimony trioxide, zinc oxide and iron oxide;carbonates such as calcium carbonate, magnesium carbonate, bariumcarbonate and strontium carbonate; sulfates such as barium sulfate,aluminum sulfate and calcium sulfate; nitrides such as aluminum nitride,silicon nitride, titanium nitride, boron nitride and manganese nitride;silicon compounds such as calcium silicate, magnesium silicate andaluminum silicate; boron compounds such as aluminum borate; zirconiumcompounds such as barium zirconate and calcium zirconate; phosphoruscompounds such as zirconium phosphate and magnesium phosphate; titaniumcompounds such as strontium titanate, calcium titanate, magnesiumtitanate, bismuth titanate, barium titanate and potassium titanate;minerals such as mica, talc, kaolin, kaolin clay, kaolinite, halloysite,cordierite, pyrophyllite, montmorillonite, sericite, amesite, bentonite,asbestos, wollastonite, sepiolite, xonotlite, zeolite, hydrotalcite,hydrated gypsum, alum, diatomaceous earth and boehmite; fly ash,dewatered sludge, glass beads, glass fibers, silica sand, magnesiumoxysulfate, silicon oxide, and silicon carbide; metals such as copper,iron, cobalt and nickel, or alloys including any of such metals;magnetic materials such as sendust, alnico magnet and ferrite; andgraphite and coke. The component (E) is preferably silica or alumina.Examples of the silica include molten silica, spherical silica,crystalline silica, amorphous silica, synthetic silica and hollowsilica, and spherical silica and crystalline silica are preferable. Thecomponent (E) may be used singly or in combination of two or more kindsthereof.

The component (E) may be particulate, and in such a case, the averageparticle size is not particularly limited, and may be, for example, 0.01μm or more and 150 μm or less, preferably 0.1 μm or more and 120 μm orless, more preferably 0.5 μm or more and 75 μm or less. Such a rangeleads to an improvement in packing ability into a mold cavity in use ofthe composition of the present invention in, for example, a sealantapplication of a semiconductor element. The average particle size of thecomponent (E) can be measured by a laser diffraction/scattering method.Specifically, the average particle size can be determined by creatingthe particle size distribution of the inorganic filler on a volumebasis, with a laser diffraction-type particle size distributionmeasuring apparatus, and defining the median size as the averageparticle size. A measurement sample that can be here used is preferablyobtained by ultrasonically dispersing the inorganic filler in water. Thelaser diffraction-type particle size distribution measuring apparatusthat can be here used is, for example, “LA-500”, “LA-750”, “LA-950” or“LA-960” manufactured by HORIBA LTD.

The compounding ratio of the component (E) is not particularly limitedand can be appropriately selected depending on its application as longas a cured product of the curable resin composition, high in heatresistance, is obtained. For example, in the case of use of thecomposition in a semiconductor-sealing application, the followingcompounding ratio is preferable.

The lower limit value of the compounding ratio of the component (E) is,for example, 150 parts by mass or more, preferably 400 parts by mass ormore, more preferably 500 parts by mass or more, based on 100 parts bymass in total of the components (A), (B), (C) and (D). The upper limitvalue of the compounding ratio of the component (E) is, for example,1300 parts by mass or less, preferably 1150 parts by mass or less, morepreferably 950 parts by mass or less. The lower limit value of thecompounding ratio of the component (E) is 400 parts by mass or more,thereby enabling an increase in amount of moisture absorption and areduction in strength according to curing of the curable resincomposition to be more suppressed, and thus enabling a cured producthaving more favorable solder cracking resistance to be obtained. Theupper limit value of the compounding ratio of the component (F) is 1300parts by mass or less, thereby allowing the curable resin composition tohave better fluidity and thus be easily packed into a mold, resulting inexertion of favorable sealing performance of a cured product.

(Component F)

The curable resin composition of the present invention may furthercontain, if desired, (F) a curing accelerator.

A known curing accelerator can be used as the curing accelerator, andexamples include amine-based compounds such as tributylamine and1,8-diazabicyclo(5,4,0)undecene-7, imidazole-based compounds such as2-methylimidazole, 2-ethylimidazole and 1,2-dimethylimidazole, andphosphororganic compounds including phosphororganic compounds withphosphorus bound by only a covalent bond, such as triphenylphosphine,and salt-type phosphororganic compounds with phosphorus bound by acovalent bond and an ionic bond, such as tetraphenylphosphoniumtetraphenylborate, but are not limited thereto. The above curingaccelerators may be used singly or in combination of two or more kindsthereof. In particular, phosphororganic compounds such astriphenylphosphine and tetra phenylphosphonium tetraphenylborate exert ahigh effect of enhancing the speed of curing and thus are preferable.

Such a phosphororganic compound described above exerts a function ofpromoting a crosslinking reaction of an epoxy group and a phenolichydroxyl group, as described in JP-S 55-457594 A. Furthermore, such aphosphororganic compound described above &so exerts a function ofpromoting a reaction of a hydroxyl group and an epoxy group generated ina cleavage reaction of (A) the multifunctional benzoxazine compound athigh temperatures. The phosphororganic compound in the present inventionis not particularly limited as long as it has the above functions,

The compounding ratio of the component (F) is preferably in a range of0.01 parts by mass or more and 10 parts by mass or less, more preferablyin a range of 0.1 parts by mass or more and 7 parts by mass or less, interms the compounding ratio of the component (F) based on 100 parts bymass in total of the components (A), (B), and (C). The component (F) canbe contained in such a range, thereby providing a curable resincomposition having more favorable fast curability.

(Other Component(s))

The composition of the present invention may contain a benzoxazinecompound other than the component (A) as long as the effects of thepresent invention are not impaired. For example, in the case where thecomposition is demanded to be reduced in viscosity, a monofunctionalbenzoxazine compound having one benzoxazine ring may be added to thecomposition.

For example, nano-carbon, a flame retardant, a release agent, acolorant, a low-stress additive, a metal hydroxide, and/or the like canbe compounded into the curable resin composition of the presentinvention as long as performances of the curable resin composition arenot impaired.

Examples of the nano-carbon include carbon nanotube, fullerene orrespective derivatives.

Examples of the flame retardant include red phosphorus, phosphates suchas triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate,cresyl diphenyl phosphate, xylenyl diphenyl phosphate, resorcinolbis-phenyl phosphate, bisphenol A bis-diphenyl phosphate, borates, andphosphazene.

Examples of release agents include: stearates; natural waxes such ascarnauba wax; synthetic waxes such as oxidized polyethylene wax; higherfatty adds such as stearic add or esters of the higher fatty adds; metalsalts such as zinc stearate; paraffin; and silicone oil.

Examples of colorants include carbon black, colcothar, and titaniumoxide.

Examples of low-stress additives include silicone oil and siliconerubber.

Examples of metal hydroxides include hydroxides such as calciumhydroxide, aluminum hydroxide, and magnesium hydroxide.

In a case where the component (E), an inorganic filler, is comprised, asilane coupling agent may be compounded together.

The compounding ratio of such other component(s) is preferably in arange of 0.01 parts by mass or more and 10 parts by mass or less, morepreferably in a range of 0.1 parts by mass or more and 7 parts by massor less in terms of the compounding ratio of such other component(s)based on 100 parts by mass in total of the components (A), (B), and (C).

[Method of Producing Curable Resin Composition]

Next, the method of producing the curable resin composition of thepresent invention is described.

The curable resin composition of the present invention can be producedby kneading or mixing the components (A) to (D), and further, ifdesired, the components (E) to (F), other cornponent(s) such as otheradditive(s), and a solvent, which are appropriately added.

The kneading or mixing method is not particularly limited, and themixing can be made using, for example, a mixing apparatus or a kneadingmachine such as a planetary mixer, a twin-screw extruder, a heat roll ora kneader, For example, in the case where the components (A), (B), and(C) are highly viscous liquids or solids at room temperature or in thecase where the component (E) is contained, if necessary, heating andkneading may be made or kneading may be made under a pressure or reducedpressure condition. The heating temperature is preferably 80 to 120° C.

The curable resin composition, which includes the component (E), is asolid at room temperature, and thus may be heated and kneaded, andthereafter cooled and pulverized to provide a powder, or the powder maybe tableted and thus formed into a pellet. The powder may also begranulated and thus formed into a granule.

In the case where the curable resin composition of the presentinvention, which does not contain any component (E), is used in anapplication of prepreg for FRP, the curable resin composition preferablyhas a viscosity of 10 to 3800 Pa·s at 50° C. The viscosity is morepreferably 10 to 2500 Pa·s, still more preferably 100 to 2000 Pa·s. Inthe case where the curable resin composition of the present invention isused in a sealant or coating application, the viscosity is notparticularly limited as long as working such as sealing or coating isnot impaired.

[Cured Product]

The cured product of the curable resin composition of the presentinvention is characterized by being high in glass transitiontemperature, being excellent in heat resistance, and being excellent inhigh-temperature stability and dimensional stability. The reason whysuch an excellent cured product is formed by the curable resincomposition of the present invention is considered as follows.

It is considered that a phenolic hydroxyl group is first produced bypolymerization in homopolymerization of benzoxazine and the phenolichydroxyl group undergoes a keto-enol tautomer at a high temperature, forexample, 200° C. or more, thereby resulting in cleavage of a polymerchain, and thus causing lower heat resistance and also a lower glasstransition temperature.

On the contrary, it is considered that the multifunctional epoxycompound having a norbornane structure and two or more epoxy groups, inthe present invention, is hardly homopolymerized and reacts with thephenolic hydroxyl group derived from benzoxazine to thereby prevent thecleavage of a polymer chain. Thus, a cured product high in heatresistance is considered to be obtained.

In addition, having a naphthylene ether type epoxy compound used incombination is considered to allow the rigid and stable structure of thepolymer crosslink to be introduced to obtain a cured product excellentin high-temperature stability and dimensional stability.

(Characteristics of Cured Product)

The heat resistance of the cured product of the present invention can beevaluated by measuring the glass transition temperature. The glasstransition temperature is, for example, 200° C. or more, preferably 205°C. or more, more preferably 210° C. or more. The glass transitiontemperature can be measured by differential scanning calorimetry (DSC).Such measurement can be simply performed by use of a commerciallyavailable differential scanning calorimeter (for example, manufacturedby HITACHI HIGH-TECH SCIENCE CORPORATION).

The dimensional stability of the cured product of the present inventioncan be evaluated by measuring the coefficient of linear thermalexpansion. The coefficient of linear thermal expansion is, for example,7.5 ppm/K or less, preferably 7.3 ppm/K or less, more preferably 7.0ppm/K or less. The coefficient of linear thermal expansion can bemeasured in accordance with JIS K7197, Testing Method for Linear ThermalExpansion Coefficient of Plastics by Thermomechanical Analysis. Suchmeasurement can be simply performed using a commercially availablethermomechanical analyzer (for example, tradename: TMA7000, manufacturedby HITACHI HIGH-TECH SCIENCE CORPORATION) in accordance with JIS K7197,Testing Method for Linear Thermal Expansion Coefficient of Plastics byThermomechanical Analysis.

The high-temperature stability of a cured product of the presentinvention can be evaluated through measurement of the temperature at athermal weight decrease rate of 10% which the cured product undergoes.The temperature at a thermal weight decrease rate of 10% which the curedproduct undergoes is, for example, 580° C. or more, preferably 590° C.or more, more preferably 600° C. or more. As used herein, thetemperature at a thermal weight decrease rate of 10% refers to atemperature which a cured product has when the weight of the curedproduct has decreased by 10% with respect to the weight the curedproduct had at the time of measurement start, wherein the temperaturehas been raised after the measurement start under dry air at a constantspeed of 10° C./minute from room temperature to 650° C. using athermogravimetry/differential thermal analyzer. Such measurement can besimply performed using a commercially availablethermogravimetry/differential thermal analyzer (for example, tradename:TG/DTA7200, manufactured by SII NANOTECHNOLOGY INC.).

[Method of Producing Cured Product]

The cured product of the present invention can be produced by performingring-opening polymerization for curing in the same curing conditions asin known benzoxazine compound and/or epoxy compound. Examples caninclude the following method.

First, the cured product can be obtained by producing the curable resincomposition of the present invention by the above method, Subsequently,heating the resulting curable resin composition can be heated at, forexample, 150 to 300° C. for a curing time of, for example, 20 seconds to5 hours, preferably 20 seconds to 1 hour, to obtain a cured product.While a treatment for a curing time of 1 to 3 minutes is sufficient forcontinuous production of the cured product, further heating for about 5minutes to 5 hours in post-curing is preferable for achievement ofhigher strength.

The cured product can also be obtained by compounding a benzoxazinecompound other than the component (A) and/or an epoxy compound otherthan the components (B) and (C), as long as the effects of the presentinvention are not impaired.

In the case where a film-shaped molded product is obtained as the curedproduct, a solvent can also be compounded to provide a composition whichhas a suitable viscosity for film formation. The solvent is notparticularly limited as long as it can dissolve the components (A) to(D) and (F), and examples thereof include hydrocarbons, ethers, estersand halogen-containing solvents.

In the case of such a solution-type curable resin composition dissolvedin the solvent, the cured product can be obtained by coating a substratewith the solution-type curable resin composition, thereaftervolatilizing the solvent, and then performing thermal curing.

[Semiconductor Device]

The semiconductor device of the present invention is a semiconductordevice where a semiconductor element is disposed in a cured productobtained by curing the curable resin composition of the presentinvention, the composition containing the components (A) to (D), and, ifdesired, the components (E), (F), and/or (an)other component(s). Thesemiconductor element is here usually supported and secured by a leadframe being a thin plate of a metallic material. The phrase“semiconductor element is disposed in a cured product” means that thesemiconductor element is sealed by a cured product of the curable resincomposition, and represents the state where the semiconductor element iscovered with the cured product. In such a case, the entire semiconductorelement may be covered, or the surface of the semiconductor elementdisposed on a base plate may be covered.

In the case where the semiconductor device is produced by sealingvarious electronic components such as a semiconductor element with thecured product of the present invention, the semiconductor device can beproduced by performing a sealing step according to a conventionalmolding method such as transfer molding, compression molding, orinjection molding.

EXAMPLES

Hereinafter, although the present invention will be specificallydescribed with reference to Examples Comparative Examples, the presentinvention is not intended to be limited to such Examples.

<Component (A); Multifunctional Benzoxazine Compound>

The following (A1) to (A2) were used in the component (A).

(A1); Phenol-diaminodiphenylmethane (P-d)-type benzoxazine representedby the following formula (2-1) (manufactured by SHIKOKU CHEMICALSCORPORATION)

(A2); Bisphenol F-aniline (F-a)-type benzoxazine represented by thefollowing formula (1-1) (manufactured by SHIKOKU CHEMICALS CORPORATION)

<Component (B); Alicyclic Epoxy Compound>

The following (B1) to (B3) were used in the component (B).

(B1) alicyclic epoxy compound 1; Compound of formula (54)

The compound (a) represented in formula (6) was synthesized according toa method described in “Shoichi Tsuchida et al., “Diels-Aider Reactionbetween Butadiene and Cyclopentadiene-Determination of Trimers-”,Journal of the Japan Petroleum Institute, 1972, Vol. 15, Issue 3, pages189 to 192”.

Next, the reaction of formula (6) was performed as follows. A reactionvessel was charged with 215 kg of chloroform and 1.6 kg of the compound(a), and 4.5 kg of meta-chloroperbenzoic add was dropped thereto withstirring at 0° C. The temperature was raised to room temperature, andthe reaction was performed for 12 hours.

Next, meta-chlorobenzoic add as a by-product was removed by filtration,and thereafter the filtrate was washed with an aqueous 1 N sodiumhydroxide solution three times and then washed with saturated saline.After the organic layer was dried over magnesium sulfate, the magnesiumsulfate was removed by filtration and the filtrate was concentrated,thereby obtaining a crude product.

To the crude product was added 2 kg of toluene, and dissolved at roomtemperature. Thereto was dropped 6 kg of heptane for crystallization,and the resultant was aged at 5° C. for 1 hour. A crystallized productwas collected by filtration and washed with hexane. The product wasdried under reduced pressure at 35° C. for 24 hours, thereby obtaining1.4 kg of a compound represented by the following formula (5-1), as awhite solid.

(B2) alicyclic epoxy compound 2; Compound (tricyclopentadiene diepoxide)of formula (5-2)

The compound (b) was synthesized as in the compound (a), according tothe method described in the above Document.

Next, the reaction of formula (7) was performed as follows, A reactionvessel was charged with 59.2 kg of chloroform and 4.0 kg of the compound(b), and 10.6 kg of meta-chloroperbenzoic add was dropped thereto withstirring at −10° C. The temperature was raised to room temperature, andthe reaction was performed for 12 hours.

Next, meta-chlorobenzoic add as a by-product was removed by filtration,and thereafter the filtrate was washed with 42.0 kg of an aqueous 5%sodium sulfite solution. The organic layer was further washed with 41.6kg of an aqueous 1 N sodium hydroxide solution four times, andthereafter washed with 48.0 kg of saturated saline. After the organiclayer was dried over magnesium sulfate, the magnesium sulfate wasremoved by filtration and the filtrate was concentrated, therebyobtaining 5.1 kg of a crude product.

To the crude product was added 3.5 kg of toluene, and dissolved at roomtemperature. Thereto was dropped 13.7 kg of heptane for crystallization,and the resultant was aged at 5° C. for 1 hour. A crystallized productwas collected by filtration and washed with heptane, The product wasdried under reduced pressure at 35° C. for 12 hours, thereby obtaining2.8 kg of a compound represented by the following formula (5-2), as awhite solid.

(B3) alicyclic epoxy compound 3; Compound (dicyclopentadiene diepoxide)of formula (5-4)

After a reaction vessel was charged with 10 kg of dicyclopentadiene, 68kg of sodium bicarbonate, 100 L of acetone and 130 L of ion exchangewater, and cooled to 10° C. or less, cooling was controlled so that thetemperature of the reaction liquid was kept at 30° C. or less, and 84 kgof axone was gradually added and the reaction was performed withstirring for 10 hours.

Next, the reaction product was extracted with 100 L of ethyl acetatetwice, and the resulting organic layers were fractionated and combined,Subsequently, the organic layer combined was washed with 100 L of amixed aqueous solution of saline and sodium thiosulfate (20% by weightof saline 20% by weight of sodium thiosulfate), and thereafter furtherwashed with 100 L of ion exchange water twice.

After the organic layer washed was dried over magnesium sulfate, themagnesium sulfate was removed by filtration, and the organic solvent wasdistilled off from the filtrate, thereby obtaining 11 kg of a compoundrepresented by the following formula (5-4), as a white solid,

<Component (C); Naphthylene Ether Type Epoxy Compound>

The following was used in the component (C).

(C); Naphthylene ether type epoxy compound (HP 6000, haying an epoxyequivalent (g/eq): 235 to 255, manufactured by DIC CORPORATION)represented by the following formula (3-7):

(wherein in the formula (3-7), the compound is a mixture of a componentrepresented by formula (3-7) wherein n is 1 and a component representedby formula (3-7) wherein n is 2).

The following (CC1) and (CC2) were used as epoxy compounds forComparative Examples,

(CC1); Epoxy compound (HP-7200, having an epoxy equivalent (g/eq): 254to 264, manufactured by DIC CORPORATION) represented by the followingformula (9):

(wherein in the formula (9), n represents an average value and is 1.41).

(CC2); Epoxy compound (HP-4710, having an epoxy equivalent (g/eq): 160to 180, manufactured by DIC CORPORATION) represented by the followingformula (10):

<Component (D); Curing Agent>

The following (D1) to (D4) were used in the component (D).

(D1); Bis(4-hydroxyphenyl)sulfide (TDP) represented by the followingformula (11-1) (manufactured by TOKYO CHEMICAL INDUSTRY CO., LTD.)

(D2); Bisphenol F represented by the following formula (11-2)(manufactured by HONSHU CHEMICAL INDUSTRY CO., LTD.)

(D3); 2,7-dihydroxynaphthalene represented by the following formula(11-3) (manufactured by TOKYO CHEMICAL INDUSTRY CO., LTD.)

(D4); Pyrogallol represented by the following formula (11-4)(manufactured by TOKYO CHEMICAL INDUSTRY CO., LTD.)

<Component (E); Inorganic Filler>

A molten spherical silica (FB-820, manufactured by DENKA COMPANYLIMITED) having an average particle size D50 of 22 μm was used in thecomponent (E).

<Component (F); Curing Accelerator>

The following was used in the component (F).

(F); Triphenylphosphine (TPP) (manufactured by HOKKO CHEMICAL INDUSTRYCO., LTD.)

<Other Components>

Carnauba wax (manufactured by CLARIANT JAPAN K.K.) as a release agentand carbon black (MA600, manufactured by MITSUBISHI CHEMICALCORPORATION) as a colorant were used.

Example 1

A curable resin composition (hereinafter, simply referred to as“composition”) and a cured product were prepared as follows, and theglass transition temperature for heat resistance evaluation, coefficientof linear thermal expansion for dimensional stability evaluation, andtemperature at a thermal weight decrease rate of 10% forhigh-temperature stability evaluation were measured.

After (A1), (B1), (C), (D1), (E), (F), carnauba wax, and carbon blackwere kneaded at a compounding ratio shown in Table 1, by use of a heatroll kneader including respective two rolls having surface temperaturesof 90° C. and 100° C. (BR-150HCV, AIMEX CO., Ltd.), under atmosphericpressure for 10 minutes, the resultant was cooled to room temperature toobtain a mixture. The mixture was pulverized for powdering by Mini SpeedMill MS-09 (manufactured by LABONECT) so that packing into a mold wasfavorably performed, thereby obtaining a composition.

<Glass Transition Temperature; Tg>

A transfer molding machine was used to cure the composition prepared, inconditions of a mold temperature of 200° C., an injection pressure of 4MPa and a curing time of 3 minutes, and the resultant was subjected toheating as a post-curing treatment in an oven at 240° C. for 4 hours,thereby producing a cured product of 3 mm length×3 mm width×15 mmheight. The cured product was cut to provide a test piece having a sizeof 3 mm length×3 mm width×2 mm height, and the test piece was used tomeasure Tg by DSC in the following conditions. The results are shown inTable 1.

Apparatus: X-DSC-7000 (manufactured by HITACHI HIGH-TECH SCIENCECORPORATION)

Measurement conditions: flow rate of N₂; 20 mL/min, rate of temperaturerise; 20° C./min

<Coefficient of Linear Thermal Expansion>

A transfer molding machine was used to cure the composition prepared, inconditions of a mold temperature of 200° C., an injection pressure of 4MPa and a curing time of 3 minutes, and the resultant was subjected toheating as a post-curing treatment in an oven at 240° C. for 4 hours,thereby producing a cured product (test piece) of 3 mm length×3 mmwidth×10 mm height.

The coefficient of linear thermal expansion of this test piece at 30 to150° C. was measured using a thermomechanical analyzer (tradename:TMA7000, manufactured by HITACHI HIGH-TECH SCIENCE CORPORATION) inaccordance with JIS K7197, Testing Method for Linear Thermal ExpansionCoefficient of Plastics by Thermomechanical Analysis, under conditions:a compression load of 20 mN and a heating rate of 10° C./minute. Theresults are shown in Table 1.

<Thermal Weight Decrease Rate>

A transfer molding machine was used to cure the composition prepared, inconditions of a mold temperature of 200° C., an injection pressure of 4MPa and a curing time of 3 minutes, and the resultant was subjected toheating as a post-curing treatment in an oven at 240° C. for 4 hours,thereby producing a cured product of 3 mm length×3 mm width×15 mmheight. The cured product was cut to provide a test piece having a sizeof 3 mm length×3 mm width×2 mm height. The obtained test piece washeated under dry air at a constant speed of 10° C./minute from roomtemperature to 650° C. using a thermogravimetry/differential thermalanalyzer (tradename: TG/DTA7200, manufactured by SII NANOTECHNOLOGYINC.), and a temperature was measured when the weight of test piece haddecreased by 10% with respect to the weight the test piece had at thetime of measurement start.

Examples 2 to 20

Each composition of the Examples was prepared in the same manner as inExample 1 except that the compounding ratio of each of the componentswas as shown in Table 1. Each composition was measured in the samemanner as in Example 1 for heat resistance (glass transitiontemperature), dimensional stability (coefficient of linear thermalexpansion), and high-temperature stability (temperature at a thermalweight decrease rate of 10%). The results are shown in Table 1.

Comparative Examples 1 to 9

Each composition of Comparative Examples was prepared in the same manneras in Example 1 except that the compounding ratio of each of thecomponents was as shown in Table 2. Each composition was measured in thesame manner as in Example 1 for heat resistance (glass transitiontemperature), dimensional stability (coefficient of linear thermalexpansion), and high-temperature stability (temperature at a thermalweight decrease rate of 10%). The results are shown in Table 2.

TABLE 1 Example Example Example Example Example Example Example 1 2 3 45 6 7 Component Multifunctional (A1) 6.4 6.0 5.7 5.4 6.0 6.7 4.7 (partsby Benzoxazine mass) Compound 1 Multifunctional (A2) BenzoxazineCompound 2 Alicyclic Epoxy (B1) 5.0 4.4 3.7 3.3 1.5 2.6 3.6 Compound 1Alicyclic Epoxy (B2) Compound 2 Alicyclic Epoxy (B3) Compound 3Naphthylene ether (C) 0.6 1.5 2.5 3.3 4.4 2.6 3.6 type Epoxy CompoundEpoxy Compound 1 (CC1) Epoxy Compound 2 (CC2) Curing Agent 1 (D1) 2.02.0 2.0 2.0 2.0 2.0 2.0 Curing Agent 2 (D2) Curing Agent 3 (D3) CuringAgent 4 (D4) Inorganic Filler (E) 85.0 85.0 85.0 85.0 85.0 85.0 85.0Curing Accelerator (F) 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Carnauba wax 0.3 0.30.3 0.3 0.3 0.3 0.3 Carbon Black 0.3 0.3 0.3 0.3 0.3 0.3 0.3 EpoxyEquivalent Ratio 1.0 1.0 1.0 1.0 1.0 0.7 1.2 Performance Heat Resistance(Glass 239 232 225 221 210 226 219 Evaluation Transition Temperature) [°C.] Dimensional Stability 7.1 6.8 7.1 7.1 6.9 6.8 6.7 (Coefficient ofLinear Thermal Expansion) [ppm/K] High-temperature Stability 581 596 608617 639 610 625 (at Thermal Weight Decrease Rate of 10%) [° C.] ExampleExample Example Example Example Example Example 8 9 10 11 12 13 14Component Multifunctional (A1) 5.9 5.5 6.9 6.5 (parts by Benzoxazinemass) Compound 1 Multifunctional (A2) 6.0 5.4 6.0 Benzoxazine Compound 2Alicyclic Epoxy (B1) 4.4 3.3 1.5 Compound 1 Alicyclic Epoxy (B2) 4.5 3.8Compound 2 Alicyclic Epoxy (B3) 3.7 3.2 Compound 3 Naphthylene ether (C)1.5 2.6 1.2 2.2 1.5 3.3 4.4 type Epoxy Compound Epoxy Compound 1 (CC1)Epoxy Compound 2 (CC2) Curing Agent 1 (D1) 2.0 2.0 2.0 2.0 2.0 2.0 2.0Curing Agent 2 (D2) Curing Agent 3 (D3) Curing Agent 4 (D4) InorganicFiller (E) 85.0 85.0 85.0 85.0 85.0 85.0 85.0 Curing Accelerator (F) 0.50.5 0.5 0.5 0.5 0.5 0.5 Carnauba wax 0.3 0.3 0.3 0.3 0.3 0.3 0.3 CarbonBlack 0.3 0.3 0.3 0.3 0.3 0.3 0.3 Epoxy Equivalent Ratio 1.0 1.0 1.0 1.01.0 1.0 1.0 Performance Heat Resistance (Glass 224 216 212 202 214 207203 Evaluation Transition Temperature) [° C.] Dimensional Stability 6.66.8 7.3 7.5 7.0 6.9 6.7 (Coefficient of Linear Thermal Expansion)[ppm/K] High-temperature Stability 599 611 587 597 593 617 636 (atThermal Weight Decrease Rate of 10%) [° C.] Example Example ExampleExample Example Example 15 16 17 18 19 20 Component Multifunctional (A1)6.3 6.9 6.6 6.6 6.1 5.9 (parts by Benzoxazine mass) Compound 1Multifunctional (A2) Benzoxazine Compound 2 Alicyclic Epoxy (B1) 3.2 1.53.3 3.4 Compound 1 Alicyclic Epoxy (B2) 1.5 Compound 2 Alicyclic Epoxy(B3) 2.8 1.5 1.5 Compound 3 Naphthylene ether (C) 3.2 2.8 3.0 3.0 3.33.4 type Epoxy Compound Epoxy Compound 1 (CC1) Epoxy Compound 2 (CC2)Curing Agent 1 (D1) Curing Agent 2 (D2) 1.3 1.4 1.3 1.3 Curing Agent 3(D3) 1.2 Curing Agent 4 (D4) 1.2 Inorganic Filler (E) 85.0 85.0 85.085.0 85.0 85.0 Curing Accelerator (F) 0.5 0.5 0.5 0.5 0.5 0.5 Carnaubawax 0.3 0.3 0.3 0.3 0.3 0.3 Carbon Black 0.3 0.3 0.3 0.3 0.3 0.3 EpoxyEquivalent Ratio 1.0 1.0 1.0 1.0 1.0 1.0 Performance Heat Resistance(Glass 225 220 224 219 220 223 Evaluation Transition Temperature) [° C.]Dimensional Stability 6.8 7.0 6.8 6.9 6.8 6.9 (Coefficient of LinearThermal Expansion) [ppm/K] High-temperature Stability 638 601 636 615635 629 (at Thermal Weight Decrease Rate of 10%) [° C.]

TABLE 2 Comparative Comparative Comparative Comparative ComparativeExample 1 Example 2 Example 3 Example 4 Example 5 ComponentMultifunctional (A1) 6.6 6.4 7.5 3.5 3.3 (parts by Benzoxazine mass)Compound 1 Multifunctional (A2) Benzoxazine Compound 2 Alicyclic Epoxy(B1) 5.3 Compound 1 Alicyclic Epoxy (B2) 5.5 Compound 2 Alicyclic Epoxy(B3) 4.4 Compound 3 Naphthylene ether (C) 8.4 type Epoxy Compound EpoxyCompound 1 (CC1) 8.6 Epoxy Compound 2 (CC2) Curing Agent 1 (D1) 2.0 2.02.0 2.0 2.0 Inorganic Filler (E) 85.0 85.0 85.0 85.0 85.0 CuringAccelerator (F) 0.5 0.5 0.5 0.5 0.5 Carnauba wax 0.3 0.3 0.3 0.3 0.3Carbon Black 0.3 0.3 0.3 0.3 0.3 Epoxy Equivalent Ratio 1.0 1.0 1.0 1.01.0 Performance Heat Resistance (Glass 257 248 223 199 175 EvaluationTransition Temperature) [° C.] Dimensional Stability 6.9 6.5 7.3 7.3 8.9(Coefficient of Linear Thermal expansion) [ppm/K] High-temperatureStability 573 578 565 644 571 (at Thermal Weight Decrease Rate of 10%)[° C.] Comparative Comparative Comparative Comparative Example 6 Example7 Example 8 Example 9 Component Multifunctional (A1) 4.2 6.0 5.3 (partsby Benzoxazine mass) Compound 1 Multifunctional (A2) 6.6 BenzoxazineCompound 2 Alicyclic Epoxy (B1) 4.4 3.3 5.3 Compound 1 Alicyclic Epoxy(B2) Compound 2 Alicyclic Epoxy (B3) Compound 3 Naphthylene ether (C)type Epoxy Compound Epoxy Compound 1 (CC1) 1.5 3.3 Epoxy Compound 2(CC2) 7.7 Curing Agent 1 (D1) 2.0 2.0 2.0 2.0 Inorganic Filler (E) 85.085.0 85.0 85.0 Curing Accelerator (F) 0.5 0.5 0.5 0.5 Carnauba wax 0.30.3 0.3 0.3 Carbon Black 0.3 0.3 0.3 0.3 Epoxy Equivalent Ratio 1.0 1.01.0 1.0 Performance Heat Resistance (Glass 189 231 219 217 EvaluationTransition Temperature) [° C.] Dimensional Stability 8.1 7.8 8.2 6.7(Coefficient of Linear Thermal expansion) [ppm/K] High-temperatureStability 583 574 579 570 (at Thermal Weight Decrease Rate of 10%) [°C.]

As shown, the cured product of the curable resin composition in eachExample has a Tg of 200° C. or more, exhibiting high heat resistance,has a coefficient of linear thermal expansion of 7.5 ppm/K or less,exhibiting excellent dimensional stability, and achieves a temperatureof 580° C. or more at a thermal weight decrease rate of 10%, exhibitingexcellent high-temperature stability. In contrast, the cured products ofthe curable resin compositions in Comparative Examples 1 to 3 areinferior in high-temperature stability; the cured product of the curableresin composition in Comparative Example 4 has low heat resistance; thecured product of the curable resin composition in Comparative Example 5is inferior in all of heat resistance, dimensional stability, andhigh-temperature stability; the cured product of the curable resincomposition in Comparative Example 6 is inferior in heat resistance andinferior dimensional stability; the cured products in ComparativeExamples 7 and 8 are inferior in dimensional stability andhigh-temperature stability; and the cured product of the curable resincomposition in Comparative Example 9 is inferior in high-temperaturestability.

The above-mentioned results have revealed that a cured product of thecurable resin composition according to an embodiment of the presentinvention is excellent in all of heat resistance, dimensional stabilityand high-temperature stability.

1. A curable resin composition containing: (A) a multifunctional benzoxazine compound having at least two benzoxazine rings, the compound being at least one multifunctional benzoxazine compound selected from a multifunctional benzoxazine compound having a structural unit of formula (1) and a multifunctional benzoxazine compound represented by a structure of formula (2), (B) an epoxy compound having at least one norbornane structure and at least two epoxy groups, (C) a naphthylene ether type epoxy compound, and (D) a curing agent;

wherein in the formula (1), R represents a linear alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms, where the aryl group optionally has halogen or a linear alkyl group having 1 to 12 carbon atoms, as a substituent; and each Z represents hydrogen, a hydrocarbon group having 1 to 8 carbon atoms and/or a linking group and is optionally the same or different, at least one Z represents a linking group, and benzoxazine rings are linked by the linking group;

wherein in the formula (2), L represents a divalent organic group having 1 to 5 aromatic rings or an alkylene group having 2 to 10 carbon atoms, and the organic group and the alkylene group optionally comprise oxygen and/or sulfur.
 2. The curable resin composition according to claim 1, wherein (C) the naphthylene ether type epoxy compound is an epoxy compound represented by a structure of formula (3):

wherein in the formula (3), n is an integer of 1 to 20; l is an integer of 0 to 2; substituents R₁ each independently represents a benzyl group, an alkyl group or a structure represented by the following general formula (3a); and R₂ independently represents a hydrogen atom or a methyl group;

wherein in the formula (3a), Ar each independently represents a phenylene group or a naphthylene group; R₂ each independently represents a hydrogen atom or a methyl group; and m is an integer of 1 or
 2. 3. The curable resin composition according to claim 1, further containing (E) an inorganic filler.
 4. The curable resin composition according claim 1, further containing (F) a curing accelerator.
 5. A cured product obtained by curing the curable resin composition according to claim
 1. 6. A semiconductor device, wherein a semiconductor element is disposed in a cured product obtained by curing the curable resin composition according to claim
 1. 7. A method of producing a curable resin composition, the method comprising the steps of: mixing (A) a multifunctional benzoxazine compound having at least two benzoxazine rings, the compound being at least one multifunctional benzoxazine compound selected from a multifunctional benzoxazine compound having a structural unit of formula (1) and a multifunctional benzoxazine compound represented by a structure of formula (2), (B) an epoxy compound having at least one norbornane structure and at least two epoxy groups, (C) a naphthylene ether type epoxy compound, and (D) a curing agent; to obtain a mixture; and processing the mixture into a powdery, pelletized, or granular curable resin composition;

wherein in the formula (1), R represents a linear alkyl group having 1 to 12 carbon atoms, a cyclic alkyl group having 3 to 8 carbon atoms, or an aryl group having 6 to 14 carbon atoms, where the aryl group optionally has halogen or a linear alkyl group having 1 to 12 carbon atoms, as a substituent; and each Z represents hydrogen, a hydrocarbon group having 1 to 8 carbon atoms and/or a linking group and is optionally the same or different, at least one Z represents a linking group, and benzoxazine rings are linked by the linking group;

wherein in the formula (2), L represents a divalent organic group having 1 to 5 aromatic rings or an alkylene group having 2 to 10 carbon atoms, and the organic group and the alkylene group optionally comprise oxygen and/or sulfur.
 8. The production method according to claim 7, wherein (C) the naphthylene ether type epoxy compound is an epoxy compound represented by formula (3):

wherein in the formula (3), n is an integer of 1 to 20; l is an integer of 0 to 2; substituents R₁ each independently represents a benzyl group, an alkyl group or a structure represented by formula (3a); and R₂ independently represents a hydrogen atom or a methyl group;

wherein in the formula (3a), Ar each independently represents a phenylene group or a naphthylene group; R₂ each independently represents a hydrogen atom or a methyl group; and m is an integer of 1 or
 2. 9. The production method according to claim 7, wherein the step of obtaining the mixture comprises further mixing (E) an inorganic filler and/or (F) a curing accelerator to obtain a mixture.
 10. A method of producing a cured product, the method comprising a step of heating the curable resin composition produced by the method according to claim 7, at 150 to 300° C. for 20 seconds to 1 hour for curing.
 11. The curable resin composition according to claim 2, further containing (E) an inorganic filler.
 12. The curable resin composition according to claim 2, further containing (F) a curing accelerator.
 13. The curable resin composition according to claim 3, further containing (F) a curing accelerator.
 14. A cured product obtained by curing the curable resin composition according to claim
 2. 15. A cured product obtained by curing the curable resin composition according to claim
 3. 16. A cured product obtained by curing the curable resin composition according to claim
 4. 17. A semiconductor device, wherein a semiconductor element is disposed in a cured product obtained by curing the curable resin composition according to claim
 2. 18. A semiconductor device, wherein a semiconductor element is disposed in a cured product obtained by curing the curable resin composition according to claim
 3. 19. A semiconductor device, wherein a semiconductor element is disposed in a cured product obtained by curing the curable resin composition according to claim
 4. 20. The production method according to claim 8, wherein the step of obtaining a mixture comprises further mixing (E) an inorganic filler and/or (F) a curing accelerator to obtain a mixture. 